Steering column device for vehicle

ABSTRACT

In a tilt and/or telescopic type steering column apparatus for a vehicle, in which a column sided bracket attached to a steering column is so provided as to be swingable and/or slidable on a car body sided bracket attached to a car body, a fastening bolt is inserted through a tilt adjustment hole formed in the car body sided bracket and through a telescopic adjustment hole formed in the column sided bracket, the two brackets are pressure-contacted to each other by fastening the fastening bolt and thus fastened in a tilt and/or telescopic adjustment position, while a tilt and/or telescopic adjustment can be made by releasing the two brackets from being pressure-contacted by slackening the fastening bolt, and each of the tilt adjustment hole and the telescopic adjustment hole has a slight gap with respect to the fastening bolt, a steering column apparatus for a vehicle is constructed such that an annular or cylindrical elastic member for preventing a backlash of the fastening bolt from being caused corresponding to the slight gap when making the tilt and/or telescopic adjustment, is fitted on an outer peripheral surface of the fastening bolt.

TECHNICAL FIELD

The present invention relates to a steering column apparatus for avehicle, which is capable of smoothly moving a fastening bolt andpreventing emission of butting noises while keeping a tilt and/ortelescopic adjustment operation preferable.

BACKGROUND ART

For example, in a tilt and/or telescopic type steering column apparatusfor a vehicle, a steering column is so constructed as to be tiltable andtelescopically slidable, and a column sided bracket (distance bracket)attached to the steering column can be pressure-contacted to a car bodysided bracket (tilt bracket) attached to a car body.

A fastening bolt is inserted through a tilt adjustment elongate holeformed in the car body sided bracket and through a telescopic adjustmentelongate hole formed in the column sided bracket. A manipulation leverof a clamp mechanism is connected to one side end of this fastening boltvia a cam mechanism and a screw mechanism. With this construction, thefastening bolt is fastened by rotating the manipulation lever in onedirection, whereby the two brackets are pressure-contacted to each otherand fixedly fastened in a tilt and/or telescopic adjustment position. Onthe other hand, the fastening bolt is slackened by rotating themanipulation lever in a reverse direction, thereby releasing the twobrackets from being pressure-contacted, the tilt and/or telescopicadjustment can be thus performed.

When making the tilt adjustment, the fastening bolt moves substantiallyin up-and-down directions together with the steering column and thecolumn sided bracket along within the tilt adjustment elongate holeformed in the car body sided bracket.

BY contrast, when making the telescopic adjustment, the steering columnand the column sided bracket move substantially in front-and-reardirections of the vehicle along within the telescopic adjustmentelongate hole in a way that gets the fastening bolt to engage with thetelescopic adjustment elongate hole.

By the way, each of the tilt adjustment elongate hole and the telescopicadjustment elongate hole has a slight gap with respect to the fasteningbolt. With this contrivance, the fastening bolt can be smoothly movedalong within the two adjustment elongate holes when making the tiltand/or telescopic adjustment, and the tilt and/or telescopic adjustmentoperation is kept preferable.

Further, when in a tilt and/or telescopic fastening operation, the carbody sided bracket and the column sided bracket are pressure-contactedto each other, and hence the backlash does not occur between the twoadjustment elongate holes and the fastening bolt even if each of thesetwo adjustment holes has such a slight gap.

When making the tilt and/or telescopic adjustment, especially when inthe tilt adjustment, the backlash between the two adjustment elongateholes and the fastening bolt and emission of butting noses, might becaused due to the slight gaps described above on the occasion of therelative movement of the fastening bolt to the two adjustment elongateholes.

DISCLOSURE OF THE INVENTION

It is an object of the present invention, which was devised under thecircumstances described above, to provide a steering column apparatusfor a vehicle, which is capable of smoothly moving a fastening bolt andpreventing emission of butting noises while keeping a tilt and/ortelescopic adjustment operation preferable.

To accomplish the above object, according to the present invention, in atilt and/or telescopic type steering column apparatus for a vehicle, inwhich a column sided bracket attached to a steering column is soprovided as to be swingable and/or slidable on a car body sided bracketattached to a car body, a fastening bolt is inserted through a tiltadjustment elongate hole or round hole formed in the car body sidedbracket and through a telescopic adjustment elongate hole or round holeformed in the column sided bracket, the two brackets arepressure-contacted to each other by fastening the fastening bolt andthus subjected to tilt- or telescopic fastening, while a tilt and/ortelescopic adjustment can be made by releasing the two brackets frombeing pressure-contacted by slackening the fastening bolt, and each ofthe tilt adjustment elongate hole or round hole and the telescopicadjustment elongate hole or round hole has a slight gap with respect tothe fastening bolt, the steering column apparatus for the vehicle ischaracterized in that an annular or cylindrical elastic member forpreventing a backlash of the fastening bolt from being causedcorresponding to the slight gap when making the tilt and/or telescopicadjustment, is fitted on an outer peripheral surface of the fasteningbolt.

Further, in the steering column apparatus for the vehicle according tothe present invention, preferably, the annular or cylindrical elasticmember can be formed of a synthetic resin.

Still further, in the steering column apparatus for the vehicleaccording to the present invention, preferably, the column sided brackethas a bottom plate portion in a position that faces the steering column,the annular or cylindrical elastic member can include an annular orcylindrical elastic support portion acting to elastically bias thefastening bolt towards the steering column from the bottom plate portionwhile abutting on the bottom plate portion and to raise the fasteningbolt by at least the gap.

According to the present invention, the annular or cylindrical elasticmember for preventing the backlash of the fastening bolt from beingcaused corresponding to the slight gap when making the tilt ortelescopic adjustment, is fitted on the outer peripheral surface of thefastening bolt. Owing to this contrivance, there is neither theoccurrence of the backlash between the two adjustment elongate holes orround holes and the fastening bolt due to the slight gap nor theemission of the butting noises on the occasion of a relative movement ofthe fastening bolt to the two adjustment elongate holes or round holeswhen making the tilt and/or telescopic adjustment.

Moreover, the fastening bolt can be smoothly moved because of nooccurrence of the backlash between the two adjustment elongate holes orround holes and the fastening bolt, and the tilt and/or telescopicadjustment operation can be kept preferable.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial sectional side view of an impact absorbing type andtilt and/or telescopic type steering column apparatus according to afirst embodiment of the present invention;

FIG. 2 is a sectional view taken along the line A-A in FIG. 1;

FIG. 3 is a sectional view (corresponding to the sectional view takenalong the line A-A in FIG. 1) of the impact absorbing type and tiltand/or telescopic type steering column apparatus according to a secondembodiment of the present invention; and

FIG. 4 is an enlarged sectional view of principal portions in FIG. 3.

EMBODIMENTS OF THE INVENTION

An impact absorbing type and tilt and/or telescopic type steering columnapparatus according to embodiments of the present invention, willhereinafter be described with reference to the drawings.

First Embodiment

FIG. 1 is a side view of the impact absorbing type and tilt and/ortelescopic type steering column apparatus according to a firstembodiment of the present invention.

FIG. 2 is a sectional view taken along the line A-A in FIG. 1.

As shown in FIG. 1, a steering shaft 2 is rotatably supported within asteering column 1. A steering wheel (unillustrated) is secured to anupper side end of the steering shaft 2.

The steering column 1 is fixedly supported onto a car body at twoportions, i.e., an upper bracket provided on a rear side of the vehicleand a lower bracket provided on a front side thereof.

The upper bracket on the rear side of the vehicle is constructed of acar body sided upper bracket 4 (tilt bracket) fixed to the car body, andof a column sided upper bracket 5 (distance bracket in FIG. 2) fixed tothe steering column 1, wherein the two upper brackets 4 and 5 arepressure-contacted to each other.

The car body sided upper bracket 4 includes U-shaped body sided plateportions 4 a, 4 a extending downward with the steering column 1interposed therebetween, flange portions 4 b, 4 b extending crosswise onboth sides from the body sided plate portions 4 a, 4 a and fixed to thecar body by use of bolts, overhanging portions 4 c, 4 c overhangingsubstantially in a C-shape toward the front of the vehicle from the bodysided plate portions 4 a, 4 a, and a suspended sustaining portion 4 dsuspended downward at an interval from the body sided plate portions 4a, 4 a.

The column sided upper bracket 5 is constructed of, as illustrated inFIG. 2, a column support portion 5 a abutting directly on a lower partof the steering column 1 and fixed thereto by welding, etc., bilateralplate portions 5 b, 5 b integral with the column support portion 5 a,extending downward and pressure-contacted by between the body sidedplate portions 4 a, 4 a of the car body sided upper bracket 4, and aninsertion plate portion 5 c (bottom plate portion) inserted in betweenlower parts of the bilateral plate portions 5 b, 5 b.

Each body sided plate portion 4 a of the car body sided upper bracket 4is formed with a tilt adjustment elongate hole 6. Each of the bilateralplate portions 5 b, 5 b of the column sided upper bracket 5 is formedwith a telescopic adjustment elongate hole 7. A fastening bolt 8 isinserted through the tilt adjustment elongate hole 6 and the telescopicadjustment elongate hole 7. A manipulation lever 9 is secured to oneside end of the tilt fastening bolt 8 by a fastening nut 9 b via anadjustment nut 9 a. These components build up a tilt and/or telescopicadjustment clamp mechanism.

Further, coating plates 10 taking substantially a U-shape and impactabsorbing plates 11 for absorbing impact energy when a secondarycollision happens, are fixed by bolts 101 to a car body sidedstrengthening member 102, depicted by oblique lines in FIG. 1, at theflanges 4 b, 4 b of the car body sided upper bracket 4.

The impact absorbing plate 11 is fixed at its proximal side end 11 a tothe car body by the bolt 11. The impact absorbing plate 11 extendsinside the substantially-C-shaped overhanging portion 4 c of the carbody sided upper bracket 4 toward the front of the vehicle, and, afterbeing bent at a circular-arc portion 11 b, extends inside theoverhanging portion 4 c toward the rear of the vehicle.

Upon the secondary collision, the impact energy acting toward the frontof the vehicle gives momentum to the car body sided upper bracket 4,with the result that the upper bracket 4 separates from the coatingplates 10 and moves together with the steering column 1 toward the frontof the vehicle.

At this moment, the impact absorbing plates 11, the proximal side ends11 a being fixed to the car body by the respective bolts 11, remain onthe car body side. On the other hand, the circular-arc portions 11 b,etc. each is subjected to a plastic deformation (drawing) within thesubstantially-C-shaped overhanging portion 4 c of the car body sidedupper bracket 4 that moves toward the front of the vehicle. The plasticdeformation (drawing) of the impact absorbing plate 11 makes it possibleto absorb the impact energy of the secondary collision. Those componentsconfigure an impact absorption mechanism.

The lower bracket on the front side of the vehicle is constructed of acolumn sided lower bracket 12 fixed to the steering column 1 and of acar body sided lower bracket 13 pressure-contacted to the lower bracket12 and fixed to the car body.

The column sided lower bracket 12 is formed with axially elongate holes27 extending in axial direction. A support pin 15 is inserted throughthe axially elongate holes 27 formed in the column sided lower bracket12 and the car body sided lower bracket 13, whereby these lower bracketsare fixed to each other by caulking. Further, an intermediate shaft 17is connected via a universal joint 16 to a vehicle-front-sided portionof the steering shaft 2.

Provided further is a balance spring 20 (or a leap-up spring for leapingup the steering column 1) for sustaining the steering column 1 so as toraise the steering column 1. The balance or leap-up spring 20 is, forexample, a coil spring and includes a couple of coil body portions 20 a,20 a (FIG. 2), a cut-off ends 21 and a fold-back portion 22 (FIG. 22).The cut-off ends 21 engage with engagement holes 23 formed in thesuspended sustaining portion 4 d of the car body sided upper bracket 4.The fold-back portion 22 (FIG. 2) is fitted with a slide member 30formed of a synthetic resin, thereby supporting the column sided upperbracket 5 upward when tilted and/or telescopically moved.

According to the first embodiment, as illustrated in FIG. 2, the tiltadjustment elongate holes 6 and the telescopic adjustment elongate holes7 each has a slight gap (Δt in FIG. 4) with respect to the fasteningbolt 8. A pair of annular elastic members 40, 40 for preventing abacklash of the fastening bolt 8 from being caused corresponding to theslight gap (Δt in FIG. 4) when making the tilt and/or telescopicadjustment, are fitted on the an outer peripheral surface of thefastening bolt 8.

Each of the annular elastic members 40, 40 is formed of a syntheticrubber. The elastic members 40, 40 have annular elastic support portions41, 41 acting to elastically bias the fastening bolt 8 toward thesteering column 1 from a bottom plate portion 5 c of the column sidedupper bracket 5 in a way that abuts on this bottom plate portion 5 c andto raise the fastening bolt 8 by at least the gap (Δt in FIG. 4). Notethat the elastic member 40 may be formed of a synthetic resin.

Accordingly, when making the tilt and/or telescopic adjustment, thefastening bolt 8 is relatively movable together with the pair of elasticmembers 40, 40 along within the two adjustment elongate holes 6, 7. Onthis occasion, there is neither the backlash between the fastening bolt8 and the two adjustment elongate holes 6, 7 due to the slight gap (Δtin FIG. 4) nor the emission of butting noises.

Further, the fastening bolt 8 can be smoothly moved because of nooccurrence of the backlash between the two adjustment elongate holes 6,7 and the fastening bolt 8. The tilt and/or telescopic adjustmentoperation can be maintained preferable.

Still further, the emission of the backlash noises due to (Δt in FIG. 4)when operated for the tilt and/or telescopic adjustment is largelyderived from a so-called stick slip, wherein the stick slip is caused atthe abutting portion between the components. The stick slip, however,could be obviated, and hence the tilt and/or telescopic adjustmentoperation can be smoothly performed.

Second Embodiment

FIG. 3 is a sectional view (corresponding to a sectional view takenalong the line A-A in FIG. 1) of impact absorbing type and tilt and/ortelescopic type steering column apparatus according to a secondembodiment of the present invention.

FIG. 4 is an enlarged sectional view of the principal portions in FIG.3.

According to the second embodiment, a cylindrical elastic member 50 forpreventing the backlash of the fastening bolt 8 from being causedcorresponding to the slight gap (Δt) when making the tilt and/ortelescopic adjustment, is fitted on the outer peripheral surface of thefastening bolt 8. The cylindrical elastic member 50, which is defined asa dedicated component, is given a more improved assembling property thanin the first embodiment involving the use of the pair of elastic members40, 40. Further, the cylindrical elastic member 50 is formed of a softsynthetic resin or rubber.

The cylindrical elastic member 50 has a plurality of elastic supportportions 51, 51 in the vicinities of bilateral end portions thereof. Theelastic support portions 51, 51 act to elastically bias the fasteningbolt 8 toward the steering column 1 from the bottom plate portion 5 c ina way that abuts on this bottom plate portion 5 c and to raise thefastening bolt 8 by at least the gap (Δt in FIG. 4).

Moreover, as shown in FIG. 4, each elastic support portion 51 is annularand pointed at an acute angle. Further, a height dimension (H) of eachelastic support portion 51 is set equal to or larger than a valueobtained by subtracting an outside diameter (φd) of the fastening bolt 8from a distance (L) from an upper side of the telescopic adjustmentelongate hole 7 down to the bottom plate portion. This setting enableseach of the elastic support portions 51, 51 to raise the fastening bolt8 by at least the gap (Δt). Note that a dimension of the gap (Δt) isdepicted in exaggeration for clarity in FIG. 4.

Accordingly, when making the tilt and/or telescopic adjustment, thefastening bolt 8 is relatively movable together with the cylindricalelastic member 50 along within the two adjustment elongate holes 6, 7.On this occasion, there is neither the backlash between the fasteningbolt 8 and the two adjustment elongate holes 6, 7 due to the slight gap(Δt) nor the emission of butting noises. Further, the fastening bolt 8can be smoothly moved because of no occurrence of the backlash betweenthe two adjustment elongate holes 6, 7 and the fastening bolt 8. Thetilt and/or telescopic adjustment operation can be maintainedpreferable. Moreover, when making the telescopic adjustment, thecylindrical elastic member 50 may be moved while rotating about thefastening bolt 8. Other configurations and effects are the same as thosein the embodiment discussed above.

Note that the present invention is not limited to the embodimentsdiscussed above and can be modified in a variety of forms. Thediscussions on the embodiments described above have dealt with the tiltand/or telescopic type steering column, however, a tilt type steeringcolumn may also be available. In this case, the car body sided bracketis formed with a tilt adjustment elongate hole, while the column sidedbracket is formed with a round hole. Moreover, a telescopic steeringcolumn may also be available. In this case, the car body sided bracketis formed with a round hole, while the column sided bracket is formedwith a telescopic adjustment elongate hole.

As discussed above, according to the present invention, the annularelastic members or the cylindrical elastic member for preventing thebacklash of the fastening bolt 8 from being caused corresponding to theslight gap when making the tilt and/or telescopic adjustment, is fittedon the outer peripheral surface of the fastening bolt. This constructionprevents the backlash between the fastening bolt and the tilt and/ortelescopic adjustment holes due to the slight gap and the emission ofbutting noises on the occasion of the relative movement of the fasteningbolt when making the tilt and/or telescopic adjustment.

Further, the fastening bolt can be smoothly moved because of nooccurrence of the backlash between the tilt and/or telescopic adjustmentholes and the fastening bolt. The tilt and/or telescopic adjustmentoperation can be maintained preferable.

1. In a tilt and/or telescopic steering column apparatus for a vehicle,in which a column side bracket attached to a steering column is soprovided as to be swingable and/or slidable on a vehicle body sidebracket attached to a vehicle body, a fastening bolt is inserted througha tilt adjustment hole formed in said vehicle body side bracket andthrough a telescopic adjustment hole formed in said column sidedbracket, said two brackets are fastened to each other with pressure byfastening said fastening bolt and thus fastened in a tilt and/ortelescopic adjustment position, while a tilt and/or telescopicadjustment can be made by releasing said two brackets from each other byloosening said fastening bolt, and said telescopic adjustment hole has aslight gap with respect to said fastening bolt, the steering columnapparatus for the vehicle being characterized in that said column sidebracket has a bottom plate portion in a position that faces saidsteering column; an annular elastic member for preventing a backlash ofsaid fastening bolt due to the slight gap when making the tilt and/ortelescopic adjustment is fitted on an outer peripheral surface of saidfastening bolt; and said annular elastic member includes an annularelastic support portion acting to elastically bias said fastening bolttowards said steering column from said bottom plate portion whileabutting on said bottom plate portion and to raise said fastening boltby at least said gap.
 2. A steering column apparatus for a vehicleaccording to claim 1, wherein said annular elastic member is formed of asynthetic resin.
 3. In a tilt steering column apparatus for a vehicle,in which a column side bracket attached to a steering column is soprovided as to be swingable on a vehicle body side bracket attached to avehicle body, a fastening bolt is inserted through a tilt adjustmenthole formed in said vehicle body side bracket and through a hole formedin said column side bracket, said two brackets are fastened to eachother with pressure by fastening said fastening bolt and thus fastenedin a tilt adjustment position, while a tilt adjustment can be made byreleasing said two brackets from each other by loosening said fasteningbolt, and said hole formed in said column side bracket has a slight gapwith respect to said fastening bolt, the steering column apparatus forthe vehicle being characterized in that said column side bracket has abottom plate portion in a position that faces said steering column; anannular or cylindrical elastic member for preventing a backlash of saidfastening bolt due to the gap when making the tilt adjustment is fittedon an outer peripheral surface of said fastening bolt; and said annularelastic member includes an annular elastic support portion acting toelastically bias said fastening bolt towards said steering column fromsaid bottom plate portion while abutting on said bottom plate portionand to raise said fastening bolt by at least said gap.
 4. In atelescopic steering column apparatus for a vehicle, in which a columnside bracket attached to a steering column is so provided as to beslidable on a vehicle body side bracket attached to a vehicle body, afastening bolt is inserted through a hole formed in said vehicle bodyside bracket and through a telescopic hole formed in said column sidebracket, said two brackets are fastened to each other with pressure byfastening said fastening bolt and thus fastened in a telescopicadjustment position, while a telescopic adjustment can be made byreleasing said two brackets from each other by loosening said fasteningbolt, and said telescopic adjustment hole formed in said column sidebracket has a slight gap with respect to said fastening bolt, thesteering column apparatus for the vehicle being characterized in thatsaid column side bracket has a bottom plate portion in a position thatfaces said steering column; an annular elastic member for preventing abacklash of said fastening bolt due to the gap when making thetelescopic adjustment is fitted on an outer peripheral surface of saidfastening bolt; and said annular elastic member includes an annularelastic support acting to elastically bias said fastening bolt towardssaid steering column from said bottom plate portion while abutting onsaid bottom plate portion and to raise said fastening bolt by at leastsaid gap.
 5. In a tilt and/or telescopic steering column apparatus for avehicle, in which a column side bracket attached to a steering column isso provided as to be swingable and/or slidable on a vehicle body sidebracket attached to a vehicle body, a fastening bolt is inserted througha hole formed in said vehicle body side bracket and through a holeformed in said column side bracket, said two brackets are fastened toeach other with pressure by fastening said fastening bolt and thusfastened in a tilt and/or telescopic adjustment position, while a tiltand/or telescopic adjustment can be made by releasing said two bracketsfrom each other by loosening said fastening bolt, and said hole formedin said column side bracket has a slight gap with respect to saidfastening bolt, the steering column apparatus for the vehicle beingcharacterized in that said column side bracket has a bottom plateportion in a position that faces said steering column; an annularelastic member for biasing said fastening bolt against the hole formedin the column side bracket is fitted on an outer peripheral surface ofsaid fastening bolt; and said annular elastic member includes an annularelastic support portion acting to elastically bias said fastening bolttowards said steering column from said bottom plate portion whileabutting on said bottom plate portion and to raise said fastening boltby at least said gap.